Riichi Calc is an easy to use app that takes any valid Japanese mahjong hand and calculates all possible winning combinations. A great companion for any Japanese mahjong player! Feel free to e-mail me about any calculation errors.
Features: • Used for the Japanese variant of Mahjong • Order is irrelevant. The app will rearrange the tiles for you • Determine waits of a tenpai hand • Provides warnings against illegal combinations (e.g. riichi with an open hand) • Calculate points using han and fu as the input • Display terminology in English or romanized Japanese
Updated on
Jul 5, 2025
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Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region, and age. The developer provided this information and may update it over time.
This app may share these data types with third parties
App activity, App info and performance, and Device or other IDs
No data collected
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Data is encrypted in transit
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Ratings and reviews
phone_androidPhone
tablet_androidTablet
4.5
356 reviews
5
4
3
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1
Hannah Staten
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July 6, 2025
edit: this is the best riichi calculator I have ever used and the developer fixed a major bug within a day. incredible work and customer support. original review which is no longer factual: used to be amazing but I can't seem to find the conditions tab anymore which is essential to score calculation. will revise to 5 stars when fixed
Richard L
July 6, 2025
Thank you for your feedback, and glad you're finding the app is useful!
Gabe Zhao
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August 17, 2025
Works for the most part, but there no 'pinfu' option to add as yaku. Sometimes there are pinfu only hands or riichi pinfu.
Alex Molina
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September 20, 2022
It a great app and functions well. There's definitely some quality of life things that could be adjusted such as being able to more conveniently mark the winning tile or at least i don't know how to do it other than inputting it last. Also it would be nice to be able to remove ads.